Volcanic Activity

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Vocabulary: magma chamber-beneath a volcano, magma is collected into a pocket
pipe-the magma moves through a long tube in the ground that connects the magma chamber through earth's surface
vent-molten rock and gas leave the volcano through an opening
lava flow-an area covered by lava as it pours out of the vent
crater-a bowl-shaped area that may form at the top of a volcano
silica-a material that is formed from the elements of oxygen and silicon
Pahoehoe-fast moving hot lava
aa-lava that is cooler and more slower-moving
pyroclastic-flow occurs when an explosion eruption hurls out ash,cinders,bombs,and gas
active-a live or occurs a lot
dormant-a sleeping or dozing object
extinct-dead,something unlikely to happen
hot spring-forms when ground water heated by a nearby body of magma
geyser-a fountain of water and steam that erupts underground
geothermal energy-a clean,reliable energy source

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Outline

How magma reaches earth's surface

• lava
  • begins as magma in mantle
    • magma forms in athenosphere

Magma Rises

• liquid magma
  • not very dense
    • rises from volcano

A Volcano Erupts

• dissolved gas
  • trapped in magma
• carbon dioxide
  • can't see it
• pressure
  • when released, carbon dioxide forms bubbles

Inside A Volcano

• Volcanoes
  • have a pocket
    • beneath surface
      • called magma chamber
• Magma
  • moves through a long tube
    • called pipe
• Inside volcanoes
  • have vents
    • lets magma pour

Characteristics of Magma

• Magma
  • thick
    • thin
• temperature
  • hot and burning
• Silica
  • helps magma burn